Electrical switching device



June 9, 1925.

P. C. SMITH ELECTRICAL SWITCHING "DEVIQE Percy 5mm,- 1

M414. Air? iiatented June 9, 1925 arse Price.

PERCY 0. SMITH, or nnsronrinen, new an'nsny, Assrcnoa ro'wnsrnn'n ELECTRIC COMPANY, moon-Penance, cr anw YORK, iv. v, conrozaarroiv 015 new YORK.

nLnotrn-rcar, swrroI-rnie DEVICE.

Applicationfiledjoecember 8,1522. Seriell'N'o. ($05,694:.

To all whom it may concern:

Be it known that I, PERCY C. SMITH, a citizen of the United States, residing at East Orange, in the county of Essex, State of New Jersey, have invented certain new and useful Improvements in Electrical Switching Devices, of which the following is a full, clear, concise, and exact descri tion. V v

This invention pertains to electrical switcl'iing devices and more particularly to such devices when applied to telephone exchange system The object of the invention is a; switchdevice for establishingconnections to a cup of circuits or trunks having-an imroyrd mechanism for assigning such cir cuits for use in a given order.

A feature of the invention relatesto a switch for establishing connections to a group of trunks having an operating member for each trunk and a circuit arrange. ment controlled by said members for allot-.

involved in telephone exchange systems, it

will be understood that it may be applied to a number of other uses.

For the purpose of explaining the construction and operation of the switch, it will be considered that it is employed to effect connections between incoming circuits such as the circuits 50 and 51 and out oin 'v circuits or trunks such as trunk 61. Each of they incoming circuits is represented by a suitable number of plain bare wires arranged in a horizontal position. Only two such circuits are shown in the drawing, the first comprising the wires 1, 2 and 3 and the second of which comprises the wires at, 5 and 6.

the following descrip-.

.tionary wires 1, 2 and 3.

- The outgoing trunks are arranged -in intersecting relation to the horizontal ciruits and each such trunk comprises a vertieal'row of flexible wire contacts. The trunk 61, for instancegappearsin the vertical row at the left in Fig. 1 and is provided with 2 set or", flexible wire contacts for each of th: horizontal incoming circuits 50, 51, etc,

1 The flexible contacts 7, 8 and 9- are secured to an insulating block 60'and project. to a point-where their free ends cooperate with the respective wires 1, 2 and 3 of-th'eihori- Zontal circuit 50. The three flexiblegwire contacts 10, 11 and 12 representing the same trunk 61 are also' 'securedito t-heblock60 and project to a point where they cooperate with the stationary wires 4, 5 and 6, ofthe second circuit 51. Similarly, trunke'til is provided with as many other sets of flexible contacts as there are horizontal circuits in the switch. The same is true of other trunks which are represented by the other vertical rows. 1 I

Flexible contacts '8 and 9 projectthrough diagonal slots 13, 14C and 15in the operating card 56 which is made of insulating material. The card 56 is supported by means of a flexible spring 58, one end of which is secured'in'the block 60 and the other end of which normally rests on the upper conductor 1 of circuit With the spring 58 resting on the conductor 1, the flexible conductors 7', 8 and 9 rest in the upper edges of the respective diagonal slots out of engagement with therespective sta- Similarly, the flexible conductors 10, 11 and 12 pass through diagonal slots 16, 17 and 18 in the operating card 57. The card 57 is supported by the spring 59 which is secured to the block 60 with its free end resting on the upper conductor 4 of the circuit 51.

Moreover, each of the outgoing trunks is provided with an individual operating bar,

three of which 19, 20 and 21 are shown. Th'e'bar 19 is individual to the trunk 61 -is' individual to the card 57 and similarly,

other fingers are provided for such other operating cards as there are for this partill ticular trunk. The same is true with remagnet 34 so as to withdraw the triggers spect to the vertical operating bars for all other trunks. Normally, the flexible-lingers 26, 27, etc. are in the position shown in Fig. 1, out of coacting relation with the respective insulating cards 56, 57, etc.

In addition to the vertical operating bars 7 19, 20 and 21, the switch is equipped with a number of horizontal intersectingbars 22, 23, etc. The bar 22 is individual to the horizontal circuit 50, the bar 23 is individual to the circuit 51 and likewise other horizontal bars (not shown) are individual to other corresponding circuits. The bar 22 is provided with a plurality of levers 23.94 and 95, etc, one arranged in proximity to an insulating car-cl relating to each of the outgoing trunks. In like fashion, the horizontaloperating bar 23 is equipped with a number of operating levers 29, 96, 97. one for each of the outgoing trunks.

'Tlie horizontal bars 22 and 23 are actuated by means of individual electromagnets 24 and 25. Both of these bars are shown in their normal or released position; The vertical bars 19, 20 and 21 are operated by individual electromagnets 47. 4S and 49. These vertical bars are also shown in their normal or released positions.

Besides the mechanism thus far described, the switch is provided with a number of selecting or'controlling cards 30, 31. 32, etc.

' These cards are made of insulating material and each is individual to one of the vertical rows of trunk contacts.

The card 30, for instance, is individual to the vertical row of contacts associated with the vertical'bar19 representing the trunk 61. The cards 31 and 32 are in like manner individual to the next two vertical rows of contacts representing the two succeeding trunks. These 'cards are provided with large openings or windows at each point. of cooperation between the sets of stationary contact wires and the flexible wire contact sets. These windows are of sutlicient size to permit the set of flexible contacts to project therethrough as best seen in Fig. 2. The purpose of these selecting cards is to cooperate with the circuit controlling springs 63, 64 and 65 in the manner to be explained hereinafter to allot the several trunks for use in a definite order.

Furthermore. the release shaft is provided in common to all operating; cards 30, 31, 32, etc. The shaft 33 carries a plurality of catches or triggers 35, 36 and 37, one for each of the operating cards. These triggers are urged toward the respective controlling cards by means of springs 33, 39 and 40. WVith the cards in their u permost positions, the triggers 35, 36 and 3 enter the respectiveslots 41. 42 and 43 and thereby hold the cards against downward movement. The shaft 33 is operated by means of an electrofrom their slots permitting the cards to fall back to their normal positions.

' If it is desired to connect one of the horizontal circuits such as the circuit 50 to one .of the outgoing trunks, a circuit is first established in any suitable manner by applying ground potential'to the start wire 66. Assuming all trunks to be idle at this tune with the controlling cards in their lowermost positions, the closure of the start wire completes a circuit thereover through the spring 63 and its lowermost contact, winding of the vertical operating magnet 47 to battery. and rotates the corresponding rod 19. The rotation of the rod 19 carries the flexible lingers 26, 27, etc. to the right as seen in Fig. 1 and under the lower edges of the respective operating cards 56, 57, etc.

Next, a circuit is established in any suitable manner for the operating magnet 24 and the bar 22 is rotated. The rotation of bar 22 carries the associated levers 28, 94 and 95 upwardly. The lever 28in its upward motion encounters the positioned flexible finger26 and the tinger'26 in turn, engages the lower edge of the card whereby'said card is moved up against the tension of the supporting spring 58. The upward movement of the card causes the flexible wires 7 8 and 9 to engage the respective conductors 1, 2 and 3 with a sliding action due to the diagonal slots 13, 14 and 15. Thus, the connection 'is established between the first idle trunk 61 and the circuit 50. Inasmuch as none of the remaining trunk bars or rodshave been positioned, the other levers 94, 95, etc., fail to encounter the corresponding flexible fingers and therefore, none of the other operating cards are disturbed.

As the operating card 56 commences its upward movement, the supporting spring 58 bears against the upper edge of the window in the common selecting card 30 and the card 30 is carried upwardly also. lVhen the card 30 has moved through a sutlicient distance, the projecting portion 44 permits the spring 63 to disengage its lower contact and to engage its upper contact. This action causes the start wire 66 to be extended through to thenext idle trunk operating magnet.

As card reaches its upper position, the trigger urged by the spring 33 enters the slot 41 and locks the card against downward movement.

As the spring 63 disengages its lower contact, the circuit of the vertical operating magnet 47 is severed and the magnet decriergizes to release the vertical bar 19. air 19 returns to its normal position carrying all of the idle' spring fingers 27, etc, which have not taken part in the establishment of the connection back out of relation with their respective operating cards '57, etc.

li iagnet 47 becomes energized Since, however, the rod 22 remains operated, lever 28 holds the spring finger 26 from restoring and as the rod returns to normal, this finger is flexed. The maintained operationof the rod 22 holds the card advanced I and preserves the connection between the circuit 50 and the trunk. 61.

When it is necessary to extend a connection from another horizontal circuit such as the circuit 51 to the next idle tr the same procedure is followed. The start wire 66 is closed to establish a circuit by wayot' the spring 63 and its upper contact, spring 64 and its lower contact through the wind ing of the next operating magnet 48 to battery. In the same manner as, already errplained, the magnet 48 rotates the bar 20 to .prepare the contacts of this trunk for operation. Following this, a horizontal operating magnet 25 is energized and the connection is established. The controlling card 31 is advanced upwardly and locks in its uppermost position releasing the spring 64 to extend the-start wire through to the next trunk magnet. After all of the trunks have seen taken in order and the last card is-lifted and locked, the next closure of the start wire 66 results in the extension of a circuit through the springs 63, 64, 65, etc. and their upper contacts, thence over conductor 67,

winding of the release magnet 34 to battery. Magnet 34 rotates rod and the locking triggers 35, 36, 37, etc. are withdrawn to permit all controlling cards which represent trunks idle at that time, to fall back to normal for use again. Controlling cards of busy. trunks will at this time be maintained in their operated positions by supporting springs such, for example, as spring 58.

In order to release an established connection, the circuit of the corresponding horizontal operating magnet 24 is opened and this magnet deenergizes to release tne associated rod 22. The rod 22 permits the lever 28 to fall back, thereby releasing spring finger 26 and permit the operating card 56 to retract, withdrawing the spring conductors 7, 8 and 9 from engagement with the corresponding horizontal conductors 1, 2 and 3.

Any suitable circuit arrangement by means of which the initiation of a call places a potential on the usual start conductor 66 and whereby the selection of the properone of the horizontal operating magnets 24, 25, etc. is effected, may be employed with a switch of this character. Reference is made, for example, to the British patent to VVestern Electric Company, Limited, No. 183,438 of 1923; which shows one manner of bringing about the closure of the starting circuit and completing circuits for the horizontal operating magnets of the switch.

The broad claims of this invention are made in my copending application Serial No. 604,977, filed December 5, 1922 which covers relative subject matter of the switching device described herein.

What isclaimed is: V,

1. In combination, a number of circuits each having separately movable contacts for making connection therewith, magnets individual to said circuits for preparing the contacts for operation, a controlling member itoreach circuit, operating means for said contacts, means controlled by said oper ating means for actuating each controlling member when the corresponding circuit is taken for use, and circuits associated with said controlling members for allotting said first mentioned circuits for use.

2. In combination, a number or trunks each having separately movable contacts for making'a connection therewith and an electromagnet for preparing said contacts for operation, a controlling element for each of said trunks, operating means for said contacts, means controlled-by said operating means for actuating each controlling element simultaneously with the operation of said contacts when the corresponding trunk is taken for use, and circuit means controlled by said elements for allotting said trunks for use in a definite order.

i 3. In combination, a number of trunks each having separately movable contacts for connection therewith, a magnet for preparing saidcon'tacts for operation, a movable card for each trunk, contact operating means, means controlled by said contact operating means for actuating said trunk card when the corresponding trunk is taken for use, and circuits controlled by said cards for allotting said trunks tornsein succession. I

I 4. In combinatiomya number or trunks each having a plurality of separately movable contacts sets, electromagnetic means for preparing said contacts for operation, operating means for actuating any contact set to make connection with the corresponding trunk, a controlling member for each trunk and common to all contact sets thereof, means controlled by said operating means for actuating said controlling member when any set of contacts to which such member is common is operated, and circuits under the control of said members for allotting said trunks for use.

5. The combination in a switching device of a number of trunks each having a plurality of separately movable contact sets for making connection therewith, cooperating bars for preparing and operating any contact set to make connection with the corresponding trunk, individual operating magnets for said bars, a controllingmember individual to each trunk, means operated by said actuating means moved effectively by said bars to operate said controlling memher when any set of contacts of the corresponding trunk are operated, and a start circuit under the control of said members for allotting said trunks for use in a given order.

6. The combination in a switching device of a number of trunks each having a plurality of contact sets, coordinate bars for preparing and separately operating any con tact set to make connection with the corresponding trunk, individual operating means for each bar, slidably movable controlling cards one for each trunk and common to all contact sets thereof, a resilient element associated with each of said contact sets and operated by said bars to effectively move one of said trunk controlling cards, and circuits under the control of said cards for allotting said. trunks for use.

7. The combination in a switching device or a number of trunks each l'iaving contacts for making connection means for operating said contacts, slidable controlling members one for each of said trunks, a resilient bar within said operating means for actuating each controlling member when the corresponding trunk is taken for use, means for locking said controlling members in their operated positions, circuit means controlled by said members for allotting the trunks for use in a definite order, and means for releasing said control ling members. i i

8. The combination in a switching device of a number of trunks each having contacts for making connection therewith, means for operating said contacts, a slidable controlling member for each trunk, a resilient bar operated by said operating means for actuating said controlling member when the corresponding trunk is taken for use, means for locking said members in, their operated therewith,

positions to identify the trunks as busy, circuit means controll d by said members for allotting the idle trunks for use in a definite order, and means for releasing said controL ling members.

9. The combination in a switching device of a number of trunks each having con tacts for making connection therewith, means for operating said contacts, slidable controlling members, one for each of said trunks, means within said operating means for actuating each of said controlling members when the corresponding trunkis taken for use, means for locking said controlling members in their operated positions, circuit means controlled by said members for allotting the trunks for use in a definite order, and means operative when all of said controlling members have been operated for releasing such r said members as correspond to idle trunks.

10. The combination in a switching device of a number of trunks, each having contacts for making connection therewith, means for operating said contacts, slidable controlling members, one for each of said trunks, resilient element within said operating means for actuating each of said controlling members when the corresponding trunk is taken for use, means for locking aid controlling members in their 0perated positions, ofi-normal contacts controlled by each of said controlling members,

means including said off-normal contacts for allotting the trunks for use in a definite order, and means for releasing said controlling members.

In witness whereof, I hereunto subscribe my name this 28th day of November A. D., 1922.

PERCY 0. SMITH. 

